Abstract:

In response to the problem of power factor non-compliance caused by different directions of active and reactive power flow after photovoltaic integration in a certain refining and chemical enterprise, and considering the actual situation of the enterprise, two solutions are proposed: capacitor shifting and coordinated control of photovoltaic inverters and capacitors. The results show that when using capacitors to compensate for reactive power, the output is a step type reactive power, there is a possibility of reactive power backflow and still a problem of different directions of active and reactive power flow. When the photovoltaic fluctuation is large, capacitors need to be switched step by step, resulting in slow response speed; when using coordinated control of photovoltaic inverters and capacitors, the power factor of the photovoltaic inverter is set to 0.98, the capacitors do not need to switch frequently, the reactive power compensation response speed is fast, there are no power flow problems, and the regional power factor meets the control requirement of 0.92. By comparing the analysis results of the two schemes, it is found that using coordinated control of photovoltaic inverters and capacitors makes power factor adjustment more convenient and reliable.

Key words: distributed photovoltaic, refining and chemical enterprises, power factor, regional electricity load, capacitor, inverter, reactive power compensation

摘要：

针对某炼化企业光伏接入后存在功率因数不达标的问题，考虑企业实际情况，提出电容器调档以及光伏逆变器和电容器协调控制两种解决方案。结果表明：当采用电容器补偿无功，输出为阶跃型无功，存在无功倒送可能性，仍存在有功、无功潮流方向不同的问题，当光伏波动较大时，电容器需逐级投切，响应速度慢；采用光伏逆变器和电容器协调控制时，光伏逆变器功率因数设定为0.98,电容器无需频繁切换，无功补偿响应速度快，无潮流问题，区域功率因数满足0.92的控制要求。通过对比两种方案分析结果，采用光伏逆变器和电容器协调控制，功率因数调节更加简便，可靠性更高。

关键词: 分布式光伏, 炼化企业, 功率因数, 区域用电负荷, 电容器, 逆变器, 无功补偿